Safety and Tolerability of Acetazolamide

Idiopathic intracranial hypertension (IIH) is a disease of unknown etiology that occurs primarily in young obese women with an estimated incidence of 0.9/100,00 in the general population1. The current medical treatment paradigm for IIH aims to decrease intracranial pressure (ICP) by decreasing the production of Cerebrospinal Fluid (CSF)2. Conventional medical management of IIH with carbonic anhydrase inhibitors (CAIs) such as acetazolamide was first suggested by Lubow and Kuhr3. Clinically, resolution of optic disc edema has been demonstrated in IIH patients using acetazolamide at 1g/d4. In 1978, a case series of 4 IIH patients in which ICP was continuously monitored before and after treatment showed that in 2 of those cases, acetazolamide at 4g/d was effective in gradually reducing ICP5 however data pertaining to safety or tolerability was not reported. In this syllabus, we examine the safety and tolerability data from the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT), presenting evidence on the type, frequency, and relative risks of experiencing AEs in patients receiving acetazolamide up to 4g/d. A discussion of SAEs that occurred during the treatment phase of the trial is also presented.